In the study, researchers asked people about their confidence levels in elementary, middle, and high school, as well as college and how they feel now. Those who were more confident earned more—and got promoted faster.

Not only that, people who described themselves as extroverted, open to experiences, agreeable, and neurotic were also more motivated and earned more than other people. We don't really get the neurotic part, but okay…

So, if you want to earn more cash (and, really—who doesn't?), be confident around the office. That means not being afraid to talk to your boss or speak up in a meeting. Your wallet will thank you.